Warning: pic heavy, as usual.
The latest member of the "Rapid Response Tactical" (or RRT) series from Jetbeam is the RRT26. This model features a continuously-variable control ring for the main white XM-L2 emitter. But it also features secondary red/green/blue LEDs – controlled in a very similar manner to the Nitecore SRT7. There are some interface differences, however, as I will describe below.
Let's see how it compares to the competition …
Manufacturer Reported Specifications:
(note: as always, these are simply what the manufacturer provides – scroll down to see my actual testing results).
- LED: CREE XM-L2 and 3 RGB auxiliary LEDs
- Runs on: 2x CR123A/RCR123A or 1x 18650 (Batteries NOT included)
- Output mode/Runtime:
- High: 980 lumens
- Low: 1 lumens / 120 hrs
- Max Beam Distance: 300 meters
- RRT magnetic control ring allows for rapid infinite brightness selection from 0 to 980 lumens
- Secondary red, green, and blue LEDs, plus police strobe and strobe
- Remaining power indicator activates in standby mode
- Tactical forward click switch with momentary power
- Detachable stainless bezel safely protects the head
- Tail stand capable (can be used as a "candle")
- Toughened ultra-clear mineral glass with double-sided anti-reflective coating
- Made of durable aircraft-grade aluminum
- Premium Type III hard-anodized anti-abrasive finish
- IPX-8 waterproof (submersible up to 2 meters)
- Impact-resistant up to 1.5 meters
- Included Accessories: holster, lanyard, rubber tail cap switch cover, and O-rings
- Dimensions: Length: 5.9" (151mm), Bezel Diameter: 1.5" (38mm), Body Diameter: 1" (25.4mm)
- Weight: 5.85 oz (166g) (excluding batteries)
- MSRP: ~$108
Packaging is similar to the Jetbeam BC25se that I recently reviewed – a simple clear plastic container, encased in a cardboard container. You have to cut open the cardboard to access the interior.
Included with the light is a basic wrist lanyard, extra o-rings, spare switch boot cover, basic holster (with Velcro closing flap), product insert and warranty card. There was no grip ring or pocket clip on my sample.
From left to right: AW Protected 18650; Jetbeam RRT26, BC25se; Nitecore SRT7, Sunwayman V25C; Eagletac G25C2-II; Sunwayman T21CS; Armytek Predator Pro v2.5.
All dimensions directly measured, and given with no batteries installed:
Jetbeam RRT26: Weight: 170.1g , Length: 151.6mm , Width (bezel): 37.6mm
Jetbeam BC25se: Weight: 133.8g, Length: 147.0mm, Width (bezel): 33.6mm
Eagletac G25C2-II (stock): Weight 141.0g, Length: 150.6mm, Width: 39.6mm
Eagletac TX25C2: Weight 93.6g, Length: 120.4mm, Width (bezel): 31.6mm
Foursevens MMX: Weight 145.8g, Length: 153.3mm, Width (bezel): 38.7mm
Klarus RS11-2014: Weight 151.5g, Length: 159mm, Width (bezel): 34.9mm
Klarus XT11-2014: Weight 140.1g, Length: 150.5mm, Width (bezel): 34.8mm
Nitecore SRT7: Weight: 172.4g, Length: 158mm, Width (bezel): 40.0m
Olight M22: Weight: 148.4g, Length: 144.8mm, Width: 41.2mm (bezel)
Sunwayman V25C: Weight: 117.3g, Length: 134.9mm, Width (bezel): 32.1mm
Zebralight SC600: Weight 87.2g, Length: 107.8mm, Width (bezel) 29.7mm
Anodizing is a dark gray, matte finish, similar to the earlier RRT-series lights from Jetbeam. Similarly, labels are a dull light gray, and so remain relatively unobtrusive. The RRT26 has a number of grip elements, including bands of knurling over the tailcap and body tube (but these are very mild, and don't do much). The knurling over the control ring is of medium aggressiveness, and hence more useful. Combined with all the ridge detail, overall grip is good. A pocket clip or grip ring would have been nice, though.
Control ring feel is very good, generally very similar to the Nitecore SRT7 (although I find the SRT7 is a bit smoother on the continuously-variable ramp portion). Like that light, there are very clear "detents" that the RRT26 ring enters into before switching through the various output modes (see my User Interface section for a discussion).
The contact board in the head features a small spring (so flat-top cells can be used just fine). The contact area of the head of the RRT26 looks a lot like my BC25se.
There are a lot of screw threads in the tail area, with a traditional fine triangular cut. Again, this tailcap is interchangeable with the BC25se tailcap. Threads are anodized, allowing for lock-out. There are thicker threads located on the head region of the battery tube (not anodized).
The RRT26 uses a forward physical clicky switch (as is common on these sorts of lights). I found the switch reasonably easy to access, with a typical traverse and feel. However, just like my BC25se, my RRT26 cannot tailstand. This is odd, given how much the tailcap rim/lanyard points project. I understood from Jetbeam that they had corrected this on the BC25se … hopefully a similar adjustment will be made here.
Unlike the Nitecore SRT7 (or Jetbeam BC25se for that matter), there is no low-voltage red LED warning indicator on the RRT26 when in use. However, you can check the at-rest charge status remaining (see user interface discussion below).
All in all, the physical build of the RRT26 is quite similar to the BC25se that I review recently – but looks more like the RRT-series of old in terms of styling and function. User interface and feature set are very close to the Nitecore SRT7, although the RRT26 is a bit smaller (and has some interface difference, see discussion below).
Like the SRT7, the RRT26 has three equidistant cut-outs along the periphery of the reflector that house tri-color LED diodes. These wells are quite deep, and well placed to minimize any beam artifacts for the main white LED beam (see beamshots later in this review).
Compared to the SRT7, I find the color LEDs are a little more "focused" for the center of the beam on the RRT26 (i.e., a bit less dispersed profile). The colored modes are also a little brighter on the RRT26, although this is hard to quantify. The red mode seems to be a truer red as well.
Note the overall size of the head is a bit smaller than the SRT7, so I would expect peak intensity throw to be lower on the RRT26.
The tri-LED effect is bound to produce some artifacts in the color beams. Again, see the beamshot section later in this review for more info.
The RRT26 has a forward tailcap clicky - press and release for momentary on, click for locked on.
Mode switching is controlled by the magnetic control ring in the head. As previously mentioned, the RRT26 features a continuously-variable interface for the main white LED. But there are actually quite a number of modes you can select on this model. Note that you can select your desired mode while the light is off, if you remember the sequence.
The various output modes on the ring are separated by very clear detents (i.e., the ring stays firmly in position, and needs a fair amount of force to move into the next mode). Starting at the far left (i.e., holding the light out in front of you, with the ring all the way counter-clockwise), as you turn the ring to the right (clockwise), you get the following outputs modes:
Blue > Green > Red > Standby off > Continuously-variable ramp (over ~200 degree turn of the ring between detents) > Max White > White Strobe.
This is basically the same as the SRT7, except you are missing the beacon and flashing color mode at the far left of the sequence.
Also, on the RRT26, there is a battery indicator feature in the Standby mode. The light will give a dim green flash every ~3.5 secs when the batteries are fully charged. Dim blue light means the cells are more than half drained. Dim red light means there is almost no power left. Note the output levels of these indicators is lower than the regular full power color modes.
Each mode is set in a clear detent of the ring (except for the continuously-variable ramp, which is between the Standby off and Max detents). This means that if you keep the ring between these two detents, you will never see any of the other modes. It is only if you exceed this range to the right (for Strobe) or left (for color modes) do you see any of these additional modes.
There is a "hidden police strobe" (which is basically just a high-frequency strobe of all color modes and the white beam). You access this by blue light mode: do two rapid turns to green and back to blue to elicit it. Turn off the light off, or turn to the white mode to return to normal functioning.
Scroll down for a discussion of the continuously-variable ramping pattern.
For information on the light, including the build and user interface, please see my video overview:
NOTE: There may some "jerkiness" of the video on some browsers. This seems to be an issue with the YouTube processing of this video for streaming. It is displaying better now on my system, but I'm not sure if the problem is gone for good.
As with all my videos, I recommend you have annotations turned on. I commonly update the commentary with additional information or clarifications before publicly releasing the video.
The RRT26 has an unusual ramping pattern, and one that is neither simply current-linear nor "visually-linear". If you aren't interested in all the technical explanations below, you can skip ahead to the beamshots.
Long time readers of my reviews will know that I have spent a lot of time categorizing the ramping patterns of different continuously-variable lights. The control mechanism can either be time-based (i.e., ramps over a range in a set time, with the ability to stop at any point), or distance-based (i.e., turn a ring to specific point to select an output, along a set degree range of levels). The RRT26 falls into the latter category, like most magnetic control ring lights.
But what truly separates continuously-variable lights is the ramping pattern – is it simply "current-linear" (meaning output changes directly proportional to current), is some sort of "visually-linear" correction used (so that the light appears to ramp evenly across our perceptual range), or some other sort of pattern? Early lights were typically current-linear, but this makes it hard to select relatively low output levels (i.e., due to the non-linear way we perceive output, these lights seem to spend most of their ramp at the near-maximal levels).
The common way to "visually-linearize" a ramp has been do a logarithmic adjustment in the circuit. Logarithms have long been used to try to compensate for a number of non-linear systems, including our relative visual perceptions (e.g. the stops of camera are logarithmic). However, it turns out that a logarithmic adjustment is not the most accurate for most relative perceptions. Extensive scientific research over the last several decades has revealed distinct power relationships that better correlate to our various relative sensory perceptions. For perceived brightness of a non-point source of light, the currently accepted linearization method is actually a cube root of output. For a full discussion of this - including detailed graphs and primary literature references - please see this post and the subsequent discussion.
To put the RRT26 into context, let's start by seeing how it compares to a couple of older lights - the Sunwayman V20C and Jetbeam RRT21. Note that I used to use a time-based scale for ring turning (i.e., the x-axis is in secs) on these older analyses - but the effect is basically the same as what I currently use (i.e., degree change).
The Jetbeam RRT21 is a classic example of circuit-linear ramp, and the Sunwayman V20C is good example of a logarithmic "visually-linear" ramp. While the RRT21 may look pretty good on the graph, this is not how it appears in real life – that light spends very little time at the low levels, making it hard to select a really low output.
Here is how the RRT26 compares to the recent Nitecore SRT7 and Sunwayman V25C in my lightbox, as you turn the ring:
As you can see, the pattern of the RRT26 looks a lot like the new V25C – the ramp has two defined phases, a typical "current-linear-like" ramp over the first half of the effective range, and a slower corrected ramp over the second half of the effective range. I'm not sure why both makers chose this pattern for their lights. Personally, I would have preferred a visually-linear ramp at the low end (for a slow ramp up from the lowest levels).
Also note that both the RRT26 and V25C show a sustained period of the ring turn where no light change occurs (i.e., the flat portion at the top of the ramp, where the light is already at max). Again, I'm not sure of the point of this – I would prefer to have had the full turn of the ring actually change output.
In any case, these direct output plots from my lightbox don't really give you a good feel for how the ramping patterns look in practice. For that, it is useful to correct the lightbox output by the actual correction factor that most closely correlates for how we perceive light (i.e., a cube-root). This is known as the Stevens’ power law relationship for perceived brightness, and is plotted below:
Again, this is what you can subjectively expect to see when you handle the lights. As expected, the more consistently "visually-linear" SRT7 will subjectively spend more time at the lower output levels than the RRT26.
Technically, the RRT26 is capable of an absolute lower low level than the SRT7. However, it is very hard to elicit these ultra-low levels - you will need to play carefully with the ring to try and find them.
In any case, I still think visually-linear ramps at the low levels would make a lot more sense for lights like the RRT26 and V25C. But again, you may not care about this level of detail, so let's move on …
Reviewer's note: I have recently updated my oscilloscope software, so the traces below may look a little different from my earlier reviews.
There is no sign of pulse-width-modulation (PWM), at any level. I presume the light is current-controlled.
The tactical strobe (white LED only) is a high pulse frequency strobe, of 13.7Hz frequency. It also has an unusual pulse width – as you can see above, there is a relatively short "off" phase (i.e. the light is on ~60% of the time). This 60:40 on/off phase differs from most strobes, which typically use a consistent 50:50 pulse width - but I do tend to see it occasionally on lights with really high strobe pulse frequencies. It doesn't make any apparent difference to how I perceive the strobe mode.
There is also a "hidden police strobe", which is basically a rapid alternating strobe of all 3 color modes and the main white LED. Sorry, I didn't try to measure the frequency.
The low-power battery indicator flash (when in white standby mode) is approximately a ~1 sec flash every ~3.5 secs or so. See below for current drain info.
Thanks the to the tailcap clicky switch, you can always turn the light completely off (i.e., no standby current).
There is a standby position on the control ring, just at the detent before the continuously-variable ramp. This standby mode also serves as the at-rest battery power indicator (as described in the UI section). I measured the current in this mode as 13.2mA on a 1x18650 (although it periodically jumps to just 14.4mA every few secs when the color LED indicator lights up, to show relative battery life remaining). Given the timings of the indicator flash, this averages out to ~13.5mA drain over time. This is fairly high, and would drain a 3100mAh 18650 battery in just under 10 days. As such, I recommend you keep the light clicked off (or locked out) at the tailcap when not in use, and just use standby/battery indicator mode when you want to know the charge status of your battery.
For white-wall beamshots below, all lights are on Max output on an AW protected 18650 battery (or RCR, as indicated). Lights are about ~0.75 meter from a white wall (with the camera ~1.25 meters back from the wall). Automatic white balance on the camera, to minimize tint differences.
Note that I am including 2xRCR for the RRT26 in the comparisons below, due to the fact that the light is significantly brighter on 2x battery sources.
The RRT26 is dimmer on 1x18650 than most modern lights in this class. However, performance on 2x sources is more in keeping with current norms. Scroll down to my actual output measures for more info.
Overall beam pattern is similar to other lights – the cut-outs for the 5mm colored emitters do not appear to be greatly affecting the spillbeam.
But let's see how the individual color beams make out:
As with the SRT7, the RGB beams are not very pretty. To be fair, ~0.75m is a ridiculously close distance to be using the light. But I keep the common distance to show you the variable nature of the artifact/interference pattern of the multi-LED setup. As you go out the greater distances, these artifacts become less noticeable, but they remain present.
I haven't shown the SRT7 color beam patterns here, because it is hard to directly compare - the SRT7 spreads out the color light over a wider area (i.e., the color modes of RRT26 have a more focused beam pattern). As a result, they would look dimmer than the RRT26 color beamshots above - even though the SRT7 is somewhat brighter on all color modes (scroll down for my testing results). If you are interested in seeing how the beam pattern shapes compare, you can check out my Nitecore SRT7 review.
All my output numbers are relative for my home-made light box setup, as described on my flashlightreviews.ca website. You can directly compare all my relative output values from different reviews - i.e. an output value of "10" in one graph is the same as "10" in another. All runtimes are done under a cooling fan, except for any extended run Lo/Min modes (i.e. >12 hours) which are done without cooling.
I have devised a method for converting my lightbox relative output values (ROV) to estimated Lumens. See my How to convert Selfbuilt's Lightbox values to Lumens thread for more info.
Throw/Output Summary Chart:
My summary tables are reported in a manner consistent with the ANSI FL-1 standard for flashlight testing. Please see http://www.flashlightreviews.ca/FL1.htm for a discussion, and a description of all the terms used in these tables. Effective July 2012, I have updated all my Peak Intensity/Beam Distance measures with a NIST-certified Extech EA31 lightmeter (orange highlights).
Let's start with the white XM-L2:
Similar to the recent BC25se from Jetbeam, the RRT26 has lower output on 1x sources compared to 2x ones. The magnitude of the difference is much greater here though, with 2xRCR being quite a bit brighter than 1x18650.
To put those results in another context, peak intensity on 2xRCR was 15,900cd (or 252m beam distance). This is at least closer to the manufacturer's report 300m beam distance (i.e., 22,500cd).
To more easily compare the differences between battery types, here is an estimated lumen comparison table:
In terms of the colored outputs, there are difficult to measure. I have previously observed that that there appears to be a difference in the sensitivity of light meters to defined wavelengths – at least compared to how these look by eye. Of course, I only have my lightbox and light meters to go by for quantitation, so here goes: below is a comparison of the outputs of the RRT26 to the SRT7 in my lightbox.
Again, these lightbox readings generally approximate what I see by eye, but I can't say if the relative calibration really holds for all specific colors. They do give you a way to generally compare the outputs between the two lights though (which is hard to do by beamshots, given their differing patterns). But note that the RRT26 is "throwier" for the color beams, so they may seem brighter at a distance.
Note: Unless otherwise stated, all my runtimes below are based on AW 2200mAh 18650 cells.
Although the max output on 1x18650 is lower than many other lights in this class, the overall regulation pattern and output/runtime efficiency are comparable to other current controlled lights (including the SRT7).
Max output on 2x sources is much higher, and the RRT26 is among the brighter lights in my collection on these sources. Output/runtime performance on 2xCR123A seems excellent. It is a bit harder to judge on 2xRCR (on Max), given the rather unique regulation pattern (i.e., the light steps down to a defined low level once the cells are somewhat depleted).
I haven't done runtimes of the color modes, but based on their tailcap current draws, I would only expect a few hours runtime in each color mode.
Max output on 1x18650 is significantly lower than on 2xCR123A/RCR.
The control ring does not use a "visually-linear" ramp of output (see discussion earlier in this review).
There are no labels to indicate where you are on the control ring. If you want to turn the light on in a specific mode, you have to remember the mode sequence and count the number of detents before activation.
The light has a physical on-off switch, so no standby current is present when clicked off or locked out at the tailcap. There is a Standby off detent on the control ring - with flashing color LEDs to serve as a battery power indicator. Note that this has a significant current, and would drain an 18650 in a matter of days (if not clicked off or locked out). As such, I recommend you only use this mode only to temporarily check the charge status of your battery.
The RRT26 is a nice update to the old RRT series from Jetbeam. In this case, it is remarkably similar in function to the SRT7 from Nitecore – just without the two blinky color modes, and with a different white output ramp format.
This design – allowing red, green, and blue light as well as a continuously-variable white light through a control ring – is good (and popular here on CPF). And you can see why: you get a versatile flashlight in much the same form factor as simpler flashlights.
The nice thing about control rings is that you can (at least roughly) tell where you are ahead of time – before you turn on the light. That said, I would also have preferred to see a more "visually-linear" ramping pattern on the RRT26 (see discussion earlier in this review). The range of color output good is nice, although it might have helped to have identifying mode labels on the head/ring (although I suppose that would clutter the look of the light).
The build is familiar – the light looks a lot like the earlier RRT series. That said, the actual screw threading and body are similar to the recent Jetbeam lights, like the BC25se.
As for beam pattern, there are significant artifacts in the colored beams (as expected), although I find the RRT26 slightly more "throwy" than the SRT7 for these modes. In terms of the main white beam, the RRT26 is very smooth and even, about typical for the class (note that the SRT7 has a white beam throw advantage due to its larger reflector). Thankfully, the color LED cut-outs of the reflector on the RRT26 don't affect the main white beam appreciably.
Performance is very good – regulation pattern and overall output/runtime efficiency are comparable to other current-controlled lights in this class. Note that max output on 1x18650 (but not 2xCR123A/RCR) is a bit low compared to other lights.
Naturally, most of this review has been comparing the RRT26 to the existing SRT7 feature set. Are there any advantages to the RRT26? Well, you have a battery indicator feature (color-coded LED flash) in the Standby mode of the RRT26. This is a cute feature to let you know the remaining charge of your battery. However, the standby/battery indicator current is higher than typical, so I don't recommend you leave the light in standby for standard use (thankfully, you can always click off the light or unscrew the tailcap to break the current). The RRT26 is also capable of a marginally lower white output modes than the SRT7 (but you would be hard pressed to reliably elicit them, given the current-linear ramp of the control ring at low output levels).
End of the day, this is another strong contender in the continuously-variable class of lights that offer multiple color modes. Hopefully you found the comparisons useful in helping you make a decision.
RRT26 provided by Jetbeam for review.